Wien filter with reduced chromatic aberration
US7164139B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 1, 2005 |
| Grant date | Jan 16, 2007 |
| Priority date | — |
| Expiry date | Feb 1, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/057
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
One embodiment disclosed relates to a Wien filter for a charged-particle beam apparatus. The charged-particle beam is transmitted through the Wien filter in a first direction. A magnetic field generation mechanism is configured to generate a magnetic field in a second direction which is perpendicular to the first direction, and an electrostatic field generation mechanism is configured to generate an electrostatic field in a third direction which is perpendicular to the first and second directions. The field generation mechanisms are further configured so as to have an offset between the positions of the magnetic and electrostatic fields along the first direction. Another embodiment disclosed relates to a Wien filter type device wherein the magnetic force is approximately twice in strength compared to the electrostatic force. Other embodiments are also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.